The Precision Extraction Solutions KPD series, built by AMG Engineering, uses PC Control and EtherCAT to optimize throughput with only four machine operators
Cannabis is, in every sense, a growth industry. Market researchers project that it will exceed $97 billion globally by 2026. Health supplements, cosmetics, food, beverage and other products containing cannabidiol (CBD), which does not create a high but offers therapeutic benefits, have helped generate the demand. However, extracting hemp-derived CBD oil at scale requires new industrial equipment, which the budding market must build from the ground up. For Troy, Michigan-based Precision Extraction Solutions, this presented significant opportunities, along with challenges due to limited industrial automation experience. When designing the new KPD series extractors, Precision® turned to AMG Inc.
“We combined our expertise in cannabis and hemp manufacturing with AMG’s expertise in agricultural processing and industrial automation,” says Nick Tennant, Founder and Chief Technology Officer at Precision®. “Our close collaboration since 2018 allowed us to build two very modular, turnkey processing centers – the KPD 1500 and the Vulcan.”
AMG is a full-service engineering consulting firm founded in 1980 to provide a wide-range of design and construction support services to various chemical processing and related heavy industrial segments. The Dayton, Ohio, company operates across the U.S. with locations in Omaha, Nebraska; Cedar Rapids, Iowa; and Chicago. AMG focuses on large agro-processing operations, particularly corn wet-milling and oil seed processing. It also recently opened the AMG Custom Controls division, a UL508A-certified panel shop. “AMG was not specifically working in the field of cannabis extraction before connecting with Precision®, but our 40-year history proves that if the product can be grown, we can engineer systems for clients to process it,” says James Davis, Business Development Administrator at AMG. “This made us the perfect fit to build the KPD machines.”
Cannabis processing moves to mega scale
With both the KPD 1500 and Vulcan, the extraction process begins with infeed of biomass, whether hemp or marijuana, using a cooling screw conveyor at -40 degrees Celsius. This ensures consistent solvent temperature and efficient extraction. The cooled biomass then enters a large stainless steel tank where counter-current ethanol extraction separates the cannabinoids. After expelling the waste biomass, the micella stream – a cannabinoid and ethanol mixture – undergoes multiple types of fine particulate filtration. Evaporation and tower reflux distillation stills vaporize the ethanol, leaving behind the pure cannabinoids, aka “crude oil.” The distilled ethanol returns to the initial holding tanks to start the process again, and the crude CBD oil enters a final holding tank for decarboxylation, which prepares it for final distillation and consumption.
At roughly 24 feet tall, 60 feet long and 9 feet wide, the KPD 1500 extraction machinery and enclosed control center fit into just seven shipping containers for use around the world. The Vulcan is slightly larger and available for use in North America. The KPD machines are far from the largest that AMG has built, but they are huge for the cannabis industry, according to Aaron Kenney, Electrical and Instrumentation Department Manager at AMG. “In this industry, many companies still produce CBD oil in small batches, similar to microbreweries or even home brewers in beer,” Kenney explains. “The KPD series, however, can process 1,500 to 4,500 kilos of biomass per day. Now companies can achieve the equivalent of mega-brewery production for CBD, which is where the cannabis market is headed.”
To enable large-scale continuous processing, the KPD machines required modular automation systems to optimize commissioning, operation and remote support. It was also important to follow Good Manufacturing Practice (GMP) and Clean in Place (CIP) standards to increase reliability and reduce downtime. The AMG engineering team wanted to use a universal platform that would provide real-time networking with deterministic control, explosion-proof hardware and intuitive operator interface technology. While researching EtherCAT solutions, AMG took a closer look at PC-based control technologies from Beckhoff Automation. “The AMG team first noticed our ATEX- and IECEx-certified EtherCAT I/O solutions, then all of the other offerings,” says Mark Mosher, Regional Sales Engineer for Beckhoff. “After many discussions and a proof of concept for the technology, AMG decided to standardize the CBD applications on Beckhoff.”
Growing more scalable and modular equipment with PC-based automation
The KPD series machines contain numerous sensors, motors, variable frequency drives (VFDs), safety switches and other components to ensure efficient and safe production. The central controller for the entire machine is a Beckhoff CX2040 Embedded PC running TwinCAT 3 automation software. Installed in the control center, the PC-based controller features an uninterruptible power supply (UPS), a 60 GB CFast card for added storage and a 2.1 GHz, quad-core Intel® Core™ i7 processor. A VPN router installed in the control center provides a secure internet connection to the CX2040, so AMG engineers can provide remote support and program updates to machines around the globe.
While AMG engineers typically used traditional hardware PLCs in the past, they quickly embraced TwinCAT as a universal engineering and runtime environment. Before the programming started in full on the Precision® project, Kenney attended a TwinCAT training at Beckhoff USA headquarters in Savage, Minnesota. He appreciates how the Beckhoff engineering platform enables programming in the object-oriented extensions of IEC 61131-3 languages, computer science standards and built-in and custom function blocks, among other tools. “As far as PLC programming software packages go, TwinCAT is very user-friendly,” he says. “Our program is a collage of ladder logic, structured text and function blocks from the built-in toolkit. Besides PLC, we programmed integrated safety logic with the TwinSAFE modules.”
EtherCAT and Automation Device Specification (ADS), a device- and vendor-neutral protocol in TwinCAT, simplified integration of third-party systems by automatically scanning and configuring devices on a network. EtherCAT remains the fastest and most open fieldbus; it offers interfaces and couplers to more than 25 top industrial networking systems, free selection of cabling topology and up to 65,535 nodes in a single network. AMG recognized this benefit when commissioning the KPD machines’ 21 variable-frequency drives (VFDs) that use AS-interface (ASi), several EtherNet/IP compressors and multiple HART devices, among others.
The wide range of EtherCAT devices from Beckhoff also includes numerous I/O terminals rated in IP20, IP67 and IP69K. The DIN rail-mounted options provide rapid communication inside the control center and explosion-proof enclosures on the machine. Machine-mountable EtherCAT Box modules allowed direct installation in the field using cables with M8 connectors and no enclosures. The wide-ranging options enabled the modularity the KPD machines required.
Operators interact with the machines via Beckhoff multi-touch HMI hardware with custom branding for Precision Extraction Systems. A 24-inch CP3924 Control Panel resides in the control center, and it connects to the CX2040 via CP-Link 4 – the One Cable Display Link. A CPX3721 Panel PC, which offers certifications for CE, ATEX and IECEx Zone 2/22, provides a robust HMI in the field. The 21.5-inch touchscreen also runs the HMI software directly on-board via a quad-core Intel Atom® processor, 8 GB DDR3L RAM and 60 GB CFast card.
“With the CPX panel, the operator on the equipment has full control to start, stop or perform other tasks locally, which was important,” Kenney says. “Then the main 24-inch touchscreen in the control room supports control and monitoring of all processes and utilities, such as air compressors, chillers, cooling towers and every piece of equipment on the KPD.”
Extraction machines with industrial automation exceed expectations
The KPD 1500 and Vulcan have achieved the necessary modularity for fast commissioning and reliable, high performance for efficient extraction at scale, according to Tennant. “The entire apparatus from Precision Extraction Solutions takes just four people to operate. Achieving this throughput from batch processing would require about 50 people and eight extractors running around the clock,” he says. “Our systems are also extremely simple, essentially plug-and-play. You can drop one onto a slab at a farm or an industrial processing facility. Automating the process as much as possible streamlines efficiencies and allows for extremely low business overhead, which grows more important as competition and regulations in this industry evolve.”
PC-based automation technologies played an important role in achieving these goals. Beyond greater programming flexibility with TwinCAT, the use of Beckhoff components cut hardware costs by 30% compared to equivalent technologies from other vendors. The CX2040 Embedded PC provides inherent connectivity to log performance data in a cloud-based historian and provide remote support as needed. This was useful when troubleshooting a recently completed KPD 1500 installed in Sicily, Italy, according to Kenney: “It saved me an 18-hour flight to fix something small.” Also, since Beckhoff has a presence in 75 countries, AMG can connect end users to local support wherever the machines are located.
Going forward, Kenney plans to expand AMG’s use of Beckhoff technologies on the KPD machines and in other areas. He hopes to upgrade the operator interface software to TwinCAT HMI and further reduce component costs by replacing the machine’s current drive technologies with Beckhoff AX8000 Servo Drives. A new VFD mode provides the same functionality while replacing two VFDs with one AX8000. In addition, when AMG Custom Controls builds electrical cabinets, it will use Beckhoff PC-based controllers and EtherCAT I/O unless customers specify otherwise.
The positive experience using this new control platform, however, was just one among many first-time experiences AMG encountered when building the KPD machines. Davis sees new experiences and new technology as standard when working in such a young industry. “Despite the challenges presented by a new and fast growing market, AMG harnessed our decades of proven expertise, along with new partnerships,” he says. “As the market and automation technologies develop, we anticipate significant room for additional growth and innovation.”
Are you interested in implementing new control and networking technologies in your processing or other equipment? Contact your local Beckhoff sales engineer today.
James Figy is the Senior Content Specialist for Beckhoff Automation LLC.